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Adult psychiatric morbidity in England: results of a household survey
Just Compensation: A No-Fault Proposal for Research-Related Injuries
Biomedical research, no matter how well designed and ethically conducted, carries uncertainties and exposes participants to risk of injury. Research injuries can range from the relatively minor to those that result in hospitalization, permanent disability, or even death. Participants might also suffer a range of economic harms related to their injuries. Unlike the vast majority of developed countries, which have implemented no-fault compensation systems, the United States continues to rely on the tort system to compensate injured research participants—an approach that is no longer morally defensible. Despite decades of US advisory panels advocating for no-fault compensation, little progress has been made. Accordingly, this article proposes a novel and necessary no-fault compensation system, grounded in the ethical notion of compensatory justice. This first-of-its-kind concrete proposal aims to treat like cases alike, offer fair compensation, and disburse compensation with maximum efficiency and minimum administrative cost. It also harmonizes national and international approaches—an increasingly important goal as research becomes more globalized, multi-site trials grow in number, and institutions and sponsors in the United States move to single-IRB review
Simulation sample sizes for Monte Carlo partial EVPI calculations
Partial expected value of perfect information (EVPI) quantifies the value of removing uncertainty about unknown parameters in a decision model. EVPIs can be computed via Monte Carlo methods. An outer loop samples values of the parameters of interest, and an inner loop samples the remaining parameters from their conditional distribution. This nested Monte Carlo approach can result in biased estimates if small numbers of inner samples are used and can require a large number of model runs for accurate partial EVPI estimates. We present a simple algorithm to estimate the EVPI bias and confidence interval width for a specified number of inner and outer samples. The algorithm uses a relatively small number of model runs (we suggest approximately 600), is quick to compute, and can help determine how many outer and inner iterations are needed for a desired level of accuracy. We test our algorithm using three case studies. (C) 2010 Elsevier B.V. All rights reserved
Electrically tunable multi-terminal SQUID-on-tip
We present a new nanoscale superconducting quantum interference device
(SQUID) whose interference pattern can be shifted electrically in-situ. The
device consists of a nanoscale four-terminal/four-junction SQUID fabricated at
the apex of a sharp pipette using a self-aligned three-step deposition of Pb.
In contrast to conventional two-terminal/two-junction SQUIDs that display
optimal sensitivity when flux biased to about a quarter of the flux quantum,
the additional terminals and junctions allow optimal sensitivity at arbitrary
applied flux, thus eliminating the magnetic field "blind spots". We demonstrate
spin sensitivity of 5 to 8 over a continuous field
range of 0 to 0.5 T, with promising applications for nanoscale scanning
magnetic imaging
The Radio Afterglow and the Host Galaxy of the X-Ray Rich GRB 981226
We report the discovery of a radio transient VLA 232937.2-235553, coincident
with the proposed X-ray afterglow for the gamma-ray burst GRB 981226. This GRB
has the highest ratio of X-ray to gamma-ray fluence of all the GRBs detected by
BeppoSAX so far and yet no corresponding optical transient was detected. The
radio light curve of VLA 232937.2-235553 is qualitatively similar to that of
several other radio afterglows. At the sub-arcsecond position provided by the
radio detection, optical imaging reveals an extended R=24.9 mag object, which
we identify as the host galaxy of GRB 981226. Afterglow models which invoke a
jet-like geometry for the outflow or require an ambient medium with a radial
density dependence, such as that produced by a wind from a massive star, are
both consistent with the radio data. Furthermore, we show that the observed
properties of the radio afterglow can explain the absence of an optical
transient without the need for large extinction local to the GRB.Comment: Accepted for publication in the Astrophysical Journal Letters.
Thirteen pages. Three Postscript figure
Molecular-orbital theory for the stopping power of atoms in the low velocity regime:the case of helium in alkali metals
A free-parameter linear-combination-of-atomic-orbitals approach is presented
for analyzing the stopping power of slow ions moving in a metal. The method is
applied to the case of He moving in alkali metals. Mean stopping powers for He
present a good agreement with local-density-approximation calculations. Our
results show important variations in the stopping power of channeled atoms with
respect to their mean values.Comment: LATEX, 3 PostScript Figures attached. Total size 0.54
Striatal dopamine D2 receptor binding of risperidone in schizophrenic patients as assessed by 123I-iodobenzamide SPECT: a comparative study with olanzapine
The aim of this investigation was to compare the degree of striatal dopamine-(D2) receptor blockade by two atypical antipsychotic drugs, risperidone and olanzapine. The percentage of D2 receptor occupancy during treatment was calculated by comparing the results of 123I-iodobenzamide SPECT with those from healthy control subjects. Twenty inpatients suffering from schizophrenia or schizoaffective psychosis according to DSM IV/ICD-10 criteria were treated with clinically recommended doses of risperidone and compared with 13 inpatients treated with up to 20 mg olanzapine. Neuroleptic dose and D2 receptor blockade correlated strongly for both risperidone (Pearson r = –0.86, p = 0.0001) and olanzapine (Pearson r = –0.77, p = 0.002). There was no significant difference between the D2 receptor occupancy of the two substances when given in the clinically recommended dose range (unpaired t-test, t= –0.112, p=0.911)
Emergent nanoscale superparamagnetism at oxide interfaces
Atomically sharp oxide heterostructures exhibit a range of novel physical
phenomena that do not occur in the parent bulk compounds. The most prominent
example is the appearance of highly conducting and superconducting states at
the interface between the band insulators LaAlO3 and SrTiO3. Here we report a
new emergent phenomenon at the LaMnO3/SrTiO3 interface in which an
antiferromagnetic insulator abruptly transforms into a magnetic state that
exhibits unexpected nanoscale superparamagnetic dynamics. Upon increasing the
thickness of LaMnO3 above five unit cells, our scanning nanoSQUID-on-tip
microscopy shows spontaneous formation of isolated magnetic islands of 10 to 50
nm diameter, which display random moment reversals by thermal activation or in
response to an in-plane magnetic field. Our charge reconstruction model of the
polar LaMnO3/SrTiO3 heterostructure describes the sharp emergence of
thermodynamic phase separation leading to nucleation of metallic ferromagnetic
islands in an insulating antiferromagnetic matrix. The model further suggests
that the nearby superparamagnetic-ferromagnetic transition can be gate tuned,
holding potential for applications in magnetic storage and spintronics
Fexofenadine is Efficacious and Safe in Children (Aged 6-11 Years) with Seasonal Allergic Rhinitis
Background: This is the first prospective, randomized, doubleblind, placebo-controlled study showing statistical improvement
of an H1-antihistamine in children with seasonal allergic rhinitis in all symptoms throughout the entire treatment period.
Objective: This randomized, placebo-controlled, parallelgroup,double-blind study was performed to assess the efficacy and safety of fexofenadine in children with seasonal allergic rhinitis.
Methods: This study was conducted at 148 centers in 15 countries. Nine hundred thirty-five children (aged 6-11 years)
were randomized and treated with either fexofenadine HCl 30 mg (n = 464) or placebo (n = 471) tablets twice a day for 14
days. Individual symptoms (sneezing; rhinorrhea; itchy nose, mouth, throat, and/or ears; itchy, watery, and/or red eyes; and nasal congestion) were assessed at baseline and then daily at 7:00 AM and 7:00 PM (±1 hour) during the double-blind treatment period. Each total symptom score was the sum of all symptoms, excluding nasal congestion. The primary efficacy
variable was the change from baseline in the average of the daily 12-hour evening reflective total symptom scores throughout
the double-blind treatment. Safety was evaluated from adverse-event reporting, vital signs, physical examinations,
and clinical laboratory data at screening and study end point
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